Branch fused cut-out block



Feb. 10, 1931. B. D. HoRToN BRANCH FUSED CUT-OUT BLOCK Original Filed Feb. 23, 19.24 2 Sheets-Sheet 1 Feb. l0, 1931. B. D. HoRToN BRANCH .FUSED CUT-OUT BLOCK Original Filed Feb. 25, 1924 2 Sheets-Sheet 2 jZUe/Z/O x Ew/JON f90/PTOM Patented Feb. 10, 1931 UNITED STATES PATENT OFFICE:l

BRYSON D. HORTON, OF DETROIT, MICHIGAN, ASSIGNOR T SQUARE D COMPANY, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN BRANCH FUSED CUT-OUT BLOCK Original application filed February 23, 1924, Serial No. 694,656. Divided and this application filed September 26, 1925.

My invention rciates to electrical service installations wherein a distributing center is eniployed to supply electric service to a number of branch load circuits, and more particuto a branch fused cut-out block having a plura.` 'ty of load `fuses and terminals for connecting the load circuits to the line circuit.

n my co-pending application. Serial Number 694,656, 'tiled February 23, 1924, of which the present application is a division, a service installation having the branch fused cut-out block, which comprises the subject matter of this application is disclosed. rFhis service installation combines a service switch with n improved type of distriliiuting center. As have stated in my copcnding application, goed engineering practice requires that the main line fuses should be rendered inaccessible, and preferably disposed in an iron clad -enciosure of the service switch, access to which is prevented by normally locking or adrig the cn Are closed. There the tine fuses ai dered inaccessible, the tional Electrical. Code requires the use of vil'iary fuses in the customers load which are. so positioned that convenient thereto may be readily had, and moreover, these auxiliary fuses are to remain unsealed but are to be provided in a metal enclosure. On other hand, it is common practice to omit Y carried to the shell of the lamp lt will be immediately apparent, when considering the requirements of such practice, that new improvements in electrical service installation will result, and these improvements extend to the branch fused cutout block in the distributing center. Heretofore, where the contractor has been obliged to obtain these units as individual parts, he may now secure them as standard equipment in the form of a unitary struct-ure. Not oniv will the service switch enclosure bo com ed with the distributing center, but the latter will include a bell ringing transformer part of the equipment, thereby overcoming the necessity for tie contracto run a separate circuit to the trancformer and place the transformer wherever convenient.

Serial No. 58,699.

Being a division of my co-pending application, the present application is directed to an improved type of branch fused cut-out block which is extremely efficient, simple and inexpensive to manufacture.

An object of my invention, therefore, is to provide a branch fused cut-out block having a plurality of fuse receptacles, so located with respect to a neutral bus bar that the branch load wires may be led in practically any direction from the block, and each branch circuit may embody but a single fuse receptacle, preferably in the live wire of the circuit. T o the neutral bus bar will be run the neutral wire of the line circuit and from this bus bar each neutral wire of the branch circuits will be taken and run to the load circuit, while. the other side of the line will run. to a common terminal connecting the fase receptacles so that the live side of each branch circuit will extend from one of these fuse receptacles.

A further object of my invention is the provision of a branch fused cut-out block of the above general type having means for quickly converting the device from a two wire to a three wire service, or vice versa.

Other objects and advantages of my invention reside in the novel form of construction, as well as in the manner of arranging the terminals and conductor straps upon the block, further objects and advantages being apparent from the following detailed description and accompanying drawings forming a part hereof:

In the drawings:

Figure l is a top plan view of a branch fused cut-out embodying my invention;

Fig. 2 is a cross sectional view taken on line 2 2 of Fig. 1;

F ig. 3 is a similar view taken on line 3-3 of Fig. l;

Fig. 4 is also a similar view but taken on line 4-4 of Fig. l; l

Fig. 5 is a top plan view of a cut-out block provided with a dead front construction to conceal the live parts on the block and to render the front thereof dead;

Fig. 6 is a wiring diagram embodying my improved branch fused cut-out in a t-wo to two-wire gang installation, having three feeders;

Fig. 7 is a wiring diagram embodying my invention in a three to two-wire electric wiring system; and

Fig. 8 is a still further form of wiring diagram in which my improved invention may be embodied, the wiring thereof being unidentified, but employing a two to two-wire electric wiring system.

The branch cut-out 5 comprises an insulating base 16comp`osed of any suitable insulating compound, on which are mounted the desired fuse receptacle terminals and their interconnections. AIn the preferred form of cut-out', herein illustrated, fuse receptacles adapted to receive the Edison plug fuses are represented, but obviously any other type of fuse could be utilized.

On the base 16, in the preferred embodiment, are positioned Edison plug fuse receptacles 17, 18, 19 and 20. Each of these fuse receptacles comprises a threaded shell Contact 21 and a center contact 22. The center contact 22 consists vof a iiat headed screw which rides a metallic washer 23, the washer 23 resting on an insulating washer 24, which in rturn rests upon a metallic extension of a conducting bar 25. This extension is in direct contact with the Vbase portion of the threaded shell contact 21. Obviously, any other construction of Edison plug fuse re'- ceptacle, or any other type, could be readily utilized. The conducting bars 25 of each fuseA receptacle terminate in wire receiving` terminals 26, 27, 28 and 29.

The center contact screws 22 of the fuse receptacles are threaded into metallic conducting bars 3() and 31, positioned in suitable recesses 32 and 33 iitted in the rear face of mounting base 16. The conducting bars and 31 are provided I with a perforation through which screws 34 are fitted, which screws extend to the top face of the mounting base 16 and are there threaded into conducting bars 35 and 36 connected to wire terminals 37 and 38. From this construction it will be evident that the center contacts 22 of the fuse receptacles 17 and 18 are made common and interconnected by their conducting bars 30 and 31, which bars are connected to the common terminal 37.

Likewise, the center contacts 22 ofthe fuse receptacles 19 and 20 are made common and interconnected by their conducting bars V30 and 31, which bars are also connected to the common terminal 38.

A conducting bar 40 constituting a neutral bus is disposed at one side of base 16, and a plurality of wire terminals 42 are connected thereto. This neutral bus 40 will in all cases be connected in the grounded neutral side of a 3 or 2-wire circuit. A depression 43 of considerable depth is pro- V16 at one side through which a suitable bolt 44 may extend in an upward direction, so that its end will thread into the bus 40.

l' wish to call attention to the particular de- -sign of base 16; of the arrangement of the various fuse receptacles; the wire receiving terminals 26, 27, 28 and 29; the removable strap 46; and the neutral bus 40, all of which are of such character that the branch cut-out will be of maximum capacity and efficiency, as well as being simple in design, and eX- ceedingly cheap to manufacture.

The wire terminals 37 and 38 are so positioned on the mounting base 16 that the medial line of their associated conduct-ing bars 35 and 36 are in substantial alignment, and consequently the wire terminals 37 and 38 `are aligned to receive, when desired, the connecting link or removable strap 46. This connecting link or removable strap 46 is fitted with apertures at either end, adapted to receive the shanks of the screws 47 and 48 associated with the wire terminals 37 and 38 respectively, which screws serve to securely interconnect the removable strap with the respective conducting bars 35 and 36 of terminals 37 and 38. With the link 46 in position, as illustrated in Figs. 1 and 6, the cut-out is arranged for two-wire service, except in Fig. 6 where the two-wire service having three feeders is used; and with the linkremoved, as shown in Fig. 7, the cutout is arranged for three-wire service, the branch circuits in such cases being arranged for two-wire service.

The branch cut-out may be secured within a distributing cabinet 6 in any suitable manner, but is preferably done byL screws such as 50 and the cooperating washers 51, which iit in suitablel depressions such as 52, positioned in the mounting base 16, so that the screws and washers will be positioned well below the top face of the mounting base 16.

If the branch cut-out is to be used with a two-wire service circuit having three feeders the connections are made as illustrated in the Fig. 6. Under these circumstances, as hereinbefore stated, the removable strap 46 is retained in position by the wire terminals 37 and 38, thereby interconnecting these two terminals and the center contacts 22 of all the receptacles.

One lead of the service circuit, coming from'the service switch, Ysuch as 53, isthen connected to either the terminal 37 or the terminal 38, and the other lead 54 of the service circuit is connected to the center terminal 42 0n the neutral bus 40.

In view of the use of the neutral bus strap and a single fuse in each branch circuit, this fuse being in the live wire of the circuit, this particular arrangement of the cut-out permits four branch circuits to be fed therefrom.

One lead of the fuse branch circuit is connected to the first Wire terminal 42, to the right of the center wire terminal on the neutral bus 40, and the other lead 56 of that branch circuit is connected to the wire terminal 27. In a like manner one lead 57 of the second branch circuit is connected to the second wire terminal 42, to the right of the center wire terminal on the neutral bus 40; and the other lead 58 of that branch circuit is connected to the other wire terminal 29. As for the third branch circuit the neutral lead 59 is connected to the rst wire terminal 42 on the left-hand side of the center wire terminal on the neutral bus 40, and the other n lead 60 of the same branch circuit is connected to the wire terminal 26. The fourth branch circuit has one of its leads 61 connected to the extreme left-hand terminal 42 on the neutral bus 40, and the other lead of this branch circuit is connected to the wire terminal 28.

Vhen the branch vfuse cut-out is thus connected, power from the service circuit, through the service switch, will be delivered to the four branch circuits over circuits which may be traced as follows.

Current will fiow 'from the serrice lead o3 to the terminal 87 or 88, thence tlnough the conducting bar at which p ir l will be divided to flow in two different cirections for supplying two branch circuits. In one instance, thc current will flow through the conducting bar 31 to the center contact- 22 of the receptacle 19, through the fuse plug' to the threaded shell contact 21, there@ through the conducting bar 25 to the wire terminal 27, and out over the branch circuit lead 56, through the branch circuit and bacl over the opposite branch circuit wire 55 te the wire terminal 42 on the nent bus 40, to which connected the opposite service lead 54. In the other instance, the current flows through the conducting bar 80 to the center contact 22 et the receptacle 20, through the fuse plug to the threaded shell contact 21, thence through the conducting bar to the terminal 29 and out over the branch circuit lead 58 through the branch circuit and back over the opposite branch circuit wire 57 to the other wire terminal 42 on the neutral bus 49, the current returning through the opposite service lead 54 to the service circuit.

For the branch circuits on the opposite side of thn block, the current flows across the interconnecting link 46 to the terminal 37,

Where it is likewise divided for delivering current to the remaining two branch circuits. The current flows over these two branch circuits in substantially the same manner as described in connection with the irst two. branch circuits. It is, therefore, deemed uunecessary to repeat the tracing ot' the current over branch circuit wires 59 and 60, and 61 and 62.

The position of the neutral bus 40 and the two wire terminals 27 and 29 permit two branch circuits to be taken ofi' the fuse cutout on the right-hand side of the installation without requiring the leads of these branch circuit-s to cross each otheron the outside ot the installation in order to be led in the proper direction over the distributing system.

In like manner the two opposite branch circuits will be led directly from the distributing cabinet 6; and one of both ot them may be led back into the switch enclosure 1, through suitable porcelain bushed knockouts 65, from which switch enclosure 1 they may then be led through conduits 66 connected to the interconnecting troughs 67, as illustrated in Fig. 6.

lWhen the service circuit is or" the threewire type, the interconnecting link 46 is removed and the apparatus is wired as illustrated in F 7 In this instance, the positive wire 68 of the three-wire circuit is connected to the wire terminal 38 (through a suitable meter load disconnecting switch 70 positioned between the meter and the branch circuits), thence to both fuse receptacles 19 and 20, terminals 27 and 29, respectively, and out over the branch circuit leads 56 and 58, through the two branch circuits, and back over the opposite leads 55 and 57, to the respective wire terminals 42 on the neutral bus 40. The neutral wire 71 passes through a. connection 72 on the service switch and connects to the center wire terminal 42 on this neutral bus 40.

The negative wire 69 of this three-wire circuit is connected through a similar meter load disconnecting switch 70, to the terminal 37, where the current is divided, flowing through the fuse receptacles 17 and 18, to the wire terminals 26 and 28, respectively, and out over the branch circuit leads 60 and 62, through the branch circuit, and out over the two opposite leads 59 and 61, and to the respective wire terminal 42 on the neutral bus 40.

The distributing cabinet 6, ei iployed in the embodiment illustrated in Fig. 7, is adapted to carry a bell transformer 75. The leads 76 and 77 of the primary circuit of this transformer may be connected to one ofthe wire terminals 42, and to either one of the terminals 87 or 38. Suitable porcelain bushings 78, provided with the proper wire connections 79, are fitted in one side of the cabinet 6, so that all that remains to be done by Workmen on the j ob is to run the bell circuit Wires from these connections 7 9 on the cabinetto the bell. The primary connections'ZG and 7 7 Will be made by the manufacturer and consequently, it will not be necessary for the contractor to install a separate circuit which must be run to the transformer, as is new the practice. rlhe transformer 75 is enclosed in a metal case, being' a part of the distributing center housed within thedistributing cabinet 6.

The embodiment shown in Fig. 8 illustrates an electrical dis'f'ributing system involving a two-wire service, having its Wires unidentified and supplying but tivo branch "circuits @no of the service leads 8O is connected to the Wire terminal 38, and the other service lead is connected tothe Wire terminal 3T. lin this instance the linlr i6 is removed and no connections to the neutral bus l0 are made.

As before explained, the code permits the omission et fuses in branch circuits on the neutral side only Where the neutral Wire is identified throughout the circuits. it the neutral Wire is unidentified, as illustrated in llig. 8, the neutral bus is preferably not used.

The fuse receptacles 17 and i9 are positioned in the opposite sides of one ot the branch circuits, these circuits being identiiied by the lead Wires 82 and 83, and the fuse receptacles 18 and 2O are positioned in the opposite sides oi the other branch circuit, which is designated by the leads 84; and 85.

These circuits may be traced as follows:

F rom the service lead 8O the current will 'low to the terminal 38 and there be divided, going one Way through the fuse receptacle i9 to the terminal 27, and over the branch circuit by Way of the branch circuit lead 82, and return by Way of the opposite branch circuit lead 88, to the terminal 26, through the inse receptacle l?, and conducting bar 3l, to the terminal 87, and back to the service switch by means of the service Wire 8l.

At the terminal 38 the current Will also flow through the conducting bar 39 to the luso 20, the terminal 29, and over the branch circuit, through the brauch circuit lead 8i, returning' by .vay orrb the opposite branch circuit 85 to the terminal 28, through the iuse receptacle 1.8 and conducting bar 30., to the terminal 37 and baclr to the service circuit over the Wire 8l.

l have hereinbetore referred to the branch iuse cut-out bloelr 5 as having a maximum capacity. rlhis is in reference to the number of branch circuits capable .of being ted from a block having a base oi the size shown.

Th. arrangement ot the Wire connecting terminals, fuse receptacles, terminals 8'? and 38 and the neutral bus ll() enter into the acomplishinent otthis feature. The terminals are spaced a maximum distance apart, with suiiicient air-spaces therebetween to prevent short circuiting of the current. ln this connection, the neutral bus l() is sunk in a recess 48, preferably oi maximum depth.` The fuse receptacle are also sunk in recesses spaced, or separated, by the upstanding projection 9() formed integrally with base 16, which is of insulating material. To prevent the branch circuit Wires Within the cabinet 6 from dropping over and upon a terminal other than the one to which it connects, recesses 91 at the tour corners oi the bloclr are provided, and in these recesses the branch circuit Wires are led and guiced. 'lo prevent the Wires of the tivo upper branch circuits from contacting `with and short Vircuiting` Vthe current across t common neutral bus llt), upstanding insulating barrierskr 92 are formed integral with the between the fuse receptacles l? and 19 and the neutral bus 40.

rllhe iront of the base i6 is preferablyY rendered dead by means of a dead front construction, comprising an insulating plate 95, suitably secured at 96 to the base 16. lnsulating plate 95 is provided with a plurality ot apertures 97 through Which the fuses 17', 18', i9 andv 20 are inserted for attachment to the fuse receptacles i7 to 20, inclusive. Thus these fuses are accessible and may be changed Without necessarily removing the plate 95. lt is desirable to permit the plate 95 toy protrude about edges et' the base l5 a distance sufficient tol prevent Contact With the live paitson the base.

All the fuse receptacles and live parts are, in reality, mbedded in the insulating base 16, and do not protrude from either the front or the rear or" the base, thereby permitting the plate 95 to lit closely against the front face and provide an inexpensive rorm of dead iront for the device shown herein. Itis considerably cheaper than forms heretofore used, say, for instance, Where insulation material is moulded especially to init over one-half ot the base and form the other half to cover protruding fuse receptacles and terminals. lt will be observed that the branch load Wire terminals 26, 27, 28 and 29 are in substantially the same plane as that O the lower portion oi' the fuse receptacles, and that the upper portion ot these fuse receptacles are below7 the front tace ot base i6. insulating barriers 92, together with surface 100, i'orm the flat trent face againstwhich the plate 95 is secured.

lt is believed that the structural principles underlying this invention, its fundamental theory and the merits and advantages it possesses will be clear to those skilled in the art Without further detailed description or elaboration of other equivalent speciiic forms in which the invention may tind expression. Hence, Without limiting the invention to any or all of the particular embodiments thereof, herein selected for purposes of illustration and description.

I claim:

l. In a device of the character described, a base member, center and shell contacts for four fuse receptacles positioned on said base member, corresponding load terminals at the corner.; of said base member connecting with said shell contacts, a bus bar on the top tace of said base member having wire connecting terminals near the ends thereof, means for connecting said center contacts with. said wire connectingterminals from the under side of said base member, and a second bus bar on said base member provided with a plurality of wire connecting terminals.

2. In a device of the character described, a base member, center and shell contacts for fuse receptacles associated with said base member, corresponding load terminals on said base member in close proximity to said receptacles and connecting to said shell contacts, a bus bar on the upper side of said base member having wire connecting terminals associated therewith, means for connecting said center contacts with said wire connecting terminals from the underside of said base member so that a single fuse plug inserted in each receptacle will be in a separate load circuit, and a common bus bar mounted on said base member having wire connecting means for the other side of each load circuit.

3. In a device of the character described, a base member, center and shell contacts for fuse receptacles mounted on said base member, a bus bar on the upper side of said base member adapted for connection to said center contacts, a second bus bar having Wire connecting terminals adapted for connection with aplurality of load circuits, each having one side only connected to said terminals, and a plurality of load terminals one for each shell Contact and to which the opposite side of each load circuit is connected.

4. In a device of the character described, a base member, center and shell contacts for fuse receptacles mounted on said base member, a pair of line terminals extending through said base member and connecting to said center contacts below said base member, a bus bar having a plurality of wire connecting terminals associated therewith, one for each load circuit connected to said base member, and interchangeable means adapted for interconnection across said line terminals whereby a two or three wire system may be eventuated, as desired, with a single fuse receptacle in each load circuit.

5. In a. device of the character described, a base member, center and shell contacts for fuse receptacles mounted on said base member, said receptacles being mounted at the corners of said base members, load terminals also at said corners connecting to said shell contacts, a. pair of line terminals having extensions running through said base member to the underside for connection with said'center contacts, each line terminal connecting *to the center contacts of two fuse receptacles, an interchangeable bus bar adapted for interconnection with said line terminals whereby a two or three wire system may be eventuated, as desired, aud a second bus bar having a common connection for the other side of eac-h load circuit.

,6. In a device et the character described,a base member, center and shell contacts for inse receptacles mounted on said base member, said center and shell contacts being recessed below the upper face of said base meinber, a load terminal connected to each shell contact in substantially the same plane as that of the lower edges of the shell contacts, a bus bar interconnecting all of the center contacts of said fuse receptacles, a second bus bar disposed in a recess at one side of said base member, and a plurality of wire connecting terminals on said second bus bar. n

7. In a device of the class described, a base member having a plurality of receptacles comprising shell and center contacts associated therewith, means on said base admitting of the connection of the center contacts of all of said receptacles, said means including a bus bar and line terminals to which the bus bar is connected, a second bus bar to which the other side of the line circuit is connected, and a plurality oit branch load circuit terminals associated with said shell contacts and said second bus bar whereby a fuse receptacle is included in one side only of each branch load circuit. v p

8. Ina device of the class described, a base member having a plurality of receptacles comprising shall and center contacts associated therewith, means carried by said base member admitting of the connection of the center contacts of all of said receptacles, a branch load circuit terminal associated with each receptacle for receiving one side of each branch load circuit, and a bus bar common to all of the branch circuits for receiving the other side of each branch load circuit whereby the latter each have but a single fuse receptacle only in one side thereof.

9. In a device of the class described, a base member having a plurality of fuse receptacles mounted thereon and below the upper side thereof, line connecting terminals on the front thereof but also recessed below said upper side, means extending through said base member into recesses in the rear of said base member, contact strips disposed in said recesses and arranged to interconnect the center contacts of said receptacles with said line terminals, other terminals in recesses in the front of said base member, said other terminals lying in appr i-:iinately the same plane with the inner portionof said receptacles, and a common terminal bus bar in a different recess in the front of said base member for providing an unfused connection for one side of each branch circuit having one of said fuse receptacles in the other side.

l0. In a device of the class described, a

base member having a plurality of fuse receptacles countersunk in the front Jface of said base member, line terminals mounted on said front face of the base member, means for interconnecting the center contacts of said receptacles With said line terminals, a load circuit terminal adjacent to each receptacle and recessed in said base member so as tov be in substantially the same plane as that of the inner portion of the receptacle, and a common terminal bus bar for receiving the other side of both the line circuit and the load circuits.

11. In a device of the class described, a base member having a plurality of fuse receptacles associated therewith, means for connecting a branch load circuit connection to each receptacle to provide a fused connection for one side of each branch load circuit, a common terminal bus bar for providing an unfused connection for the neutral side of each branch load circuit, a line terminal connection for l said bus bar, other line terminal connections mounted on said base member and adapted for connection to s aid receptacles, and means associated With sald last line terminal connections Which provides for accommodatlng v either a two or three Wire system, as desired.

12. In a branch fuse cut-out adapted for interconnection in tWo or three Wire electric distributing systems i'or'supplying four tvvo Wire branch circuits, in combination, an insulating base, apparatus 0n said base, said apparatus including a fuse receptacle for one side only of each branch circuitand a common neutral bus4 for the opposite side of each branch circuit, and interconnecting means adapted to make common all of said fuse receptacles. y

In Witness whereof, I have hereunto subscribed my name.

BRYSON'D. HOR'ION. 

